More assignment refinements

Author: jussienko

numpy/broadcast-translation/README.md

@@ -1,5 +1,8 @@
 ## Translation with broadcasting
 
+NumPy broadcasting is powerful tool for dealing with different, but compatible
+shape arrays.
+
 File [points_circle.dat](points_circle.dat) contains x, y coordinates along a
 circle. Translate all the coordinates with some vector e.g. (2.1, 1.1). Plot
 both the original and translated points in order to see the effect of

numpy/finite-difference/README.md

@@ -1,5 +1,7 @@
 ## Finite-difference
 
+Vectorization is crucial for obtaining good performance with NumPy.
+
 Derivatives can be calculated numerically with the finite-difference method
 as:
 

numpy/integration/README.md

@@ -17,6 +17,6 @@ x'_i = (x_i + x_{i-1}) / 2
 
 ![img](https://quicklatex.com/cache3/09/ql_f124fd5c831e873c6abd41160fae2d09_l3.png)
 
-Use the same interval as in the first exercise and investigate how much the
+Calculate the integral in the interval [0,π/2] and investigate how much the
 Riemann sum of **sin** differs from 1.0. Avoid `for` loops. Investigate also
 how the results changes with the choice of Δx.